I was using CrashPlan too and I have converted my repositories to a common duplicacy storage.
To support different backup schedules, I do backup some folders in the user profile using an own snapshot-id, and so I have several snapshots per machine. All snapshots have some different filters and a common filter base set.
I use the preference nobackup_file to exclude these folders in the backup of the user profile.

In my fork at github, I have extended the filter file syntax with a new statement to include another filter file.
Using @<filename>, you can now include other files. Relative paths are supported.
In addition I have changed the exclude behavior for the .duplicacy folder. When using nobackup_file, this folder will not get excluded anymore. I use filters that exclude cache and internal files (see this post).

at the moment the location of the entry point for the filter file is still fixed to .duplicacy/filters. The location is not configurable in the preferences file.

Indeed you can now keep all configuration in a small tree outside the data and use the include-feature to streamline your filter configuration, instead of duplicating all filters into all repository configurations. But you will still need separate configuration directories to use different filters for different snapshots.

I know this is possible to define a filters file to filter what will or will not be backup for every repository. But I would like to use one global filter for all my repository, using CLI or the new WEB-UI.
I didn’t see anything on that in the documentation. Is it possible ?

This would also be nice if we could use a global filter file as a base to append repository-specific filters to. My use case would be to exclude files and folders that I never want to back up in any repository (e.g., temporary files, Lightroom thumbnails, macOS files and folders like .DS_Store, and many others that I otherwise have to keep up to date for each repo).